The role of cytosolic sialidase in developing enamel organs.

胞质唾液酸酶在牙釉质器官发育中的作用。

• 批准号: 09671845
• 负责人: AKITA Hirotoshi
• 金额: $ 2.05万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09671845/
• 关键词: sialoglycoconjugate; cytosolic sialidase; enamel organ; in situ hybridization; immunocytochemistry; lectin-cytochemistry; transmission eletron microscope; rat; 歯胚上皮; 免疫組織化学; レクチン組織化学; 骨格筋細胞; 上皮性歯胚

We obtained following results in in situ hybridization, immunocytochemical, and lectincytochemical studies of rat molar tooth germs.(1) in situ hybridization study : The level of cytosolic sialidase-mRNAs changed largely with cell differentiation. It was high in the oral epithelium, outer and inner enamel epithelium, and dental papilla. It was very low or barely detectable in the stellate reticulum and transitional cells between the oral epithelium and the outer enamel epithelium, suggesting its steep drop in transition. Although the overall image of the mRNA expression was high in dental papilla, the mesenchymal cells expressed different levels of the mRNAs from each other.(2) immunocytochemical study : Every cell expressed high levels of cytosolic sialidase-protein in the oral epithelium, enamel organ and dental papilla. The enzyme protein was localized in the cytoplasm, nucleoplasm and mitochondrial matrix of each cell. Its Iocalization pattern was very similar to that in skeletal m … More uscle cells of rats, suggesting it being ubiquitous in many types of cells. Based on the number of immunogold particles, the amount of the enzyme protein did not largely change in cells during the course of cell differentiation. In this point of view the expression of the enzyme protein was different from that of the mRNA.(3) lectin-cytochemical study : Lectin (Limax flavus)-binding sites were numerous on the cell surface and in the extracellular matrix of tooth germs. However the number of them were small in the cytoplasm. We examined whether a small number of those binding sites were meaningful or not. An inhibitory sugar was effective in decreasing the binding sites at about a half level, indicating the presence of putative cytoplasmic sialoglycoconjugates. The possibility of non-specific lectin binding to the cytoplasm remains to be excluded by conducting a supplementary experiment in which the binding sites are expected to decrease in tissue sections digested by cytosolic sialidase. Less

本实验对大鼠磨牙牙胚进行了原位杂交、免疫细胞化学和凝集细胞化学研究，获得了以下结果。(1)原位杂交研究：唾液酸酶mRNA水平随细胞分化而变化。在口腔上皮、内外釉上皮和牙乳头中含量较高。在口腔上皮和外釉上皮之间的星状网状层和过渡细胞中，它非常低或几乎检测不到，表明它在过渡中急剧下降。虽然mRNA表达的整体图像在牙乳头中是高的，但是间充质细胞表达彼此不同水平的mRNA。(2)免疫细胞化学研究：口腔上皮、成釉器和牙乳头中的每一个细胞都表达高水平的唾液酸酶蛋白。酶蛋白定位于细胞质、核质和线粒体基质中。它的定位模式与骨骼肌非常相似， ...更多信息 大鼠的肌细胞，表明它在许多类型的细胞中普遍存在。根据免疫金颗粒的数量，在细胞分化过程中，酶蛋白的量在细胞中没有很大变化。从这个角度来看，酶蛋白的表达不同于mRNA的表达。(3)凝集素细胞化学研究：在牙胚的细胞表面和细胞外基质中有许多凝集素（Limax flavus）结合位点。但在细胞质中数量较少。我们检查了这些结合位点中的一小部分是否有意义。抑制性糖是有效的，在减少约一半的水平，表明推定的细胞质sialoglycoconjugates的存在下的结合位点。非特异性凝集素与细胞质结合的可能性仍有待通过进行补充实验来排除，在该实验中，结合位点预计在细胞溶质唾液酸酶消化的组织切片中减少。少

项目成果

Kazuo Hanzawa (米澤 和雄): "Oral manifestations and long-trem observations of active Paget's disease of bone." J.Bone Miner.Metab.16・4. 264-270 (1998)

Kazuo Hanzawa (Kazuo Yonezawa)：“活动性佩吉特骨病的口腔表现和长期观察。J.Bone Miner.Metab.16・4 (1998)。

Tadashi Wada: "Cloning, expression, and chromosomal mapping of a human ganglioside sialidase"Biochemical and Biophysical Research Communications. 261・1. 21-27 (1999)

和田正：“人神经节苷脂唾液酸酶的克隆、表达和染色体定位”《生物化学和生物物理研究通讯》261·1（1999）。